Many different types of medical procedures involve the use of tethers. For example, tethers may be used to tighten or compress tissue (e.g., by bringing two pieces or sections of tissue together). The tissue may be, for example, soft tissue, such as muscle tissue or fat tissue. As an example, in some tissue tightening procedures, anchors coupled to a tether are embedded in tissue, and the tether is then pulled upon to provide a cinching effect that tightens or compresses the tissue via the anchors. Examples of devices and methods for such procedures applied to heart valve repair are described, for example, in U.S. Patent Application Publication Nos. US 2006/0122633 A1, US 2006/0190030 A1, and US 2008/0172035 A1, all of which are hereby incorporated by reference in their entirety.
Some methods of tissue tightening or compression include threading a tether through two pieces of tissue, applying tension to the tether, and tying off or knotting the tether to maintain the tension. Extra tether material may then be cut and removed. However, the manipulation required when knotting, tying, and/or cutting a tether can be difficult (e.g., because of restricted space). Moreover, certain methods may not adequately maintain tension in a tether. Additionally, some methods of knotting, tying, and/or cutting a tether may be unduly complicated and/or time-consuming.
Accordingly, it would be desirable to provide methods and devices for effectively locking and/or cutting a tether to help maintain tension in the tether. It would further be desirable for such methods and devices to be relatively easy and/or efficient to use.